Process of obtaining metals and compounds thereof.



No. 333,472. PATENTED 001?. 16, 1906.

ILMEHNER.

PROCESS OF OBTAINING METALS AND COMPOUNDS THEREOF.

APPLICATION IILBP FEB. 18. 1904.

. INVENTOR; W.'1'-Ess;s: HERMANN MEHNER (1.1m QM v vaporsior instance, such as molten silicates (including slag, scoria, cinder, andjthe like) UNITED STATES PATENT HERMANN MEHNER, OF BERLIN, GERMANY. PnocEsspF OBTAINING METALS AND COMPOUNDS THEREOF.

Specification of Letters Patent.

Patented Oct. 1b, 4.

Application filed February 18, 1904. Serial K0 1943791 To all, whom it may concern:

Be it known that I, HERMANN MEHNER, doctor of philosophy, a subject of the King of Saxony, whose post-office address is No. 1 Koniggratzerstrasse, Berlin, Prussia, German Empire, have invented a new and useful Process of Obtainin Metals and Compounds Thereof; and I do diereby declare that the following is a full, clear, and exact description of my invention, which will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to the process of extracting metals from ores. and other com- 1pounds by means of the combined action of eat and reducing agents; and it has .for its object to so improve this process that the extraction of such metals as then are set free in the state of vapors as, for instance, zinc, sodium, potassium, and others well known to chemistsand the dry hot production of compounds thereof will be largely deprived of the thermical inconveniences connected with the usual method of supplying the heat, as well as from other disadvantages connected therewith. Taking the extraction ofzinc after the usual distillation process as an example, this process is carriedout in retorts, and the heat is supplied through the walls of the latter. It is well known to those skilled in the art that this supply of heat cannot be effected but with reat'losses, that those losses gave to metall urgists the idea of carrying out the process in shaft-furnaces, and thatthe attempts to do this have failed because of the incapability of the known heating methods to supply the furnace with the large amount of heat at all or at a tolerable cost. Now I have found. that those difl-iculties can be overcome with ease and great advantage bybringing the ores or. compounds while under the action of the reducing agent in contact with an incandescent fluid heat-carrier incapable of' absorbing or otherwise injuring the metallic or a molten metal, as iI( )I1-tl1c hcat-ciu'rior being heated above its melting-point up to i incandescence. l Starting, for instance, from tln. decomposition of zinc oxid. by means ol carbon,

which takes place according to the equation ZnO-l-G CO-I-Zn,

andladmitting the cold state, then the thermic equation will be 85,800 calories +28,800 calories equals The escaping carbon monoxid produced. having a molecular heat of 6.8. takes with it from the turnace at 1,200" centigrade 6.8X1,200 equals 8,1600.

The escaping zinc-vapors. having a molecular heat of 5, take with them from the furnace 5 x 1,200 equals I; 0,0000.

57,000 0. ,(kilogram calories.)

To be added for vaporization heat of the zinc and losses by radiation round twenty-six per cent 18,880 C.

ing a specific heat of 0.3 and a specific weight of 3.0is capable of transmitting nine hun' dred calories for each degre centigrade by which it is cooled or ninety housand calories by causing it to cool by centi adethat is, the amount of heat requ red or producing sixty-five kilograms of.zincit is .readily understood how much the process is improved as regards utilization of heat. In applying instead of silicates molten and highly-heatediron the thermic efi'ect will be still greater, and, moreover, the use of iron is attended with another important advantage 1n working sulluncontammg ores, as will be pointed out later on. The essence of my present invention therefore consists in a broad sense in bringing in contact with each other the compound or compounds whereof the metal is to be extracted, the reducing agent, and an incandescent fluid heat-carrier of such a nature as not to absorb or otherwise do harm to the metallic vapors generated. h

The heat-carrier will prel'erably consist of a molten silicate (including slag, scoria, cin- (Ir-rs, and the like) heated above its meltingpoint up lo im-amlesccncc or a molten metal heated above its nclLingoi.it up to incandcsccncc, especially iron; but any other serviceable substance may be used, and thcrefore I do not limit myself to the use of silicates and metals. It silicates are used, the melting-point thereof can easily be re ur lated by the addition of alkalies. r

The in'iprtwed process may be carried out in several Ways, and I proceed to describe some of them, taking zinc. as the metal to be extra. ed from zinc ore, which may be gab i'ncv, zinc-blendc, zinc-glance, or any other ire, including the so-called composite lac process may be arried out by chargan ordinary shalt-imamce with a mixture zinc ore and an excess of carbon (coal, coke. bitumen, asphalt, pitch, and the like) and causing a curre t oi a molten silicate l d up to incandescencc, preferably to :1 i1 cherry-red. at least, to percolato t 'ouca the said mixture. l, however, prerm to charge the furnace with carbon alone and to add the Zinc ore to the molten slag or other incandescent ljluid, thus using the same as a combined heat and ore carrier. Morem-cr, i. meter to so direct the inllma'ing current as to cause the same to take its path through the central. or core portionot the contents of the furnace.

The mixture of zinc-vapors generated and carboi ionoxid resulting from the carbon absorl o by the reducing process arcmiuscd to escape from the upper portion of the furnace into a condenser to be separated.

The zinc-vapors are obtained in as dense a state as in the usual distillation process,

- being only attenuated by such a quantity of carbon monoxid as corresponds to the equation vwith bricks of dense carbon, which do not absorb zinc-vapors or allow the vapors to penetrate them. Moreover, they are not at tacked chemically, owing to the reducing atmosphere which is existing in the furnace, and do not react with the current o1 silicate, which -for the most part otits path passes at a distance from the Walls.

The silicate escaping from the lows part of the furnace is coilected, heated anew to a bright cherry-red at least, mixed with a fresh quantity of ore, corresponding to that composed in the preceding operation, and then returned to the upper portion of the furnace. From this it is evident that such losses of zinc as are caused in the ordinary zinc-distillation process by incomplete reaction and entrance of zinc into the slag or l other residues of the process are avoided, as any remainder of Zinc ore, as Well as any ab sorbed zinc, are returned to the furnace.

The heating of the silicate may be carried l out in a cupola-furnace, preferably such as is used for making slag for the production of slagwool. and then the fuel should be as free as possible from mineral substances, so as not to contaminate the silicate, or the bee ting oi thc'silicate may be eli'ected by means of producer-gas in apparatus similar to a converter, or any other suitable heating method may be made use of.

(Du the annexed sheet I have illustrated in a. mere soheniatical manner a com binationof apparatus suitable for carrying out my improved process, the decomposing-furnace, the reheatbig-furnace, and their connection i being shown in cross section.

(1 is the tlecomposing-furnace, being a shaftiurnace provided on top with a. hopper Z) for supplying it with coke or a mixture of coke and Zinc ore r and with a ccntrally-located inlet. d for the incandescent slag e, the hopper being closed by a. sealedlid b. At one side of the bottom, which is slightly inclined, the hatb'turnace has an outlet for the used lag c", which is received by a transportable vessel-"tor instance, a truck or cinder-tub g.

7t is the reheatingdnrnacc, preferably a rererbcratory furnace of well-known type having a door 'i. through which it is supplied with the used slag to be reheated, and a taphole it: for discharging the reheated slag into the slutt -furnace (1 the slagdnlet d of the latter being connected with said tap-hole through a pipe Z. Near its top the shaftfurnace a is provided with an outlet m for the metallic vapors generated therein, the condenser for said vapors and its connection With the outlet in being omitted from the dren case the ore contains besides zinc other metals-such as lead, silver, copper, and others, as frequently oco .'s-or is a so-called composite ore then tllOSo metals will collect on the bottom of the furnace below the silicate, and the mixture may be tapped off through a tap-hole at suitable intervals and separated into its constituents by the aid of Well-known methods.

furnace will not be attended with a sensible cost, as will readily be seen from the following consideration: Su posing the distance between the outletan the inlet for the silicats to be six meters and one cubic meter of the silicate having the specific Weight 3.0 to Weigh three thousand kilograms to be used for producing sixty-five kilograms zinc in one hour, then to lift those three thousand kiiograms there are required eighteen thousand meter kilograms per hour or 18,000+ 3,600: 5 meter kilograms per secondtl1at The return of the reheated silicate to the i molten metal heated above its meltingoint up to incandescence. As such I pre er'to use iron, as this metal is by itself a reducing agent for zinc ores, especially zinc-blends and zinc-glance. In case of sulfur-containing zinc ores I prefer to charge ashaftfurnave with a mixture of coal and zinc ore or with zinc ore alone and to cause a current of molten iron heated to at least'a bright cherryred to percolate through the mixture. The

. iron by its contact with the ore drives out the zinc in the state of vapors and combines withthe sulfur contained in the ore. The mixture of zinc vapors and gases or the zincvapors alone are caused to pass into a sepa rator. The molten iron escaping from the lower portion of the furnace is collected and reheated by means of the absorbed sulfur,

this being effected by blowing .a current of air. through the iron, whereby the sulfur is burned t6 sulfur dioxid, which'leaves the iron in the gaseous state, and maybe collect; ed for use. The reheated iron is then returned to thefurnace. v

As will readily be understood by those skilled in the art, my present invention may be used for driving'outany distillable metals from com ounds. Such metals are, for instance, sodium, potassium, quicksilver, cadmium, and-arsenic, and,,moreover, there is no doubt that metals of a higher vaporization-point those canwith advantage be distilled-from compounds and ores b means of myimproved process, and the mo tenand highly-heated metallic heat-carrier may also; be used for at once absorbing-the metallic vapors-for instance,.to form alloys. I have already in a general sense referred to the use of my improved process for pro ducing metallic compounds. This will be done by admitting to the furnace such gas-- eous reagents as are capable of at once com-' bining with the metallic vapors generated. For instance, if it is desired toproduce pure zinc sulfid from zinc ores for use as a'paint sulfur is vaporized outside of the furnace, and the sulfur-vapors are led-into thefurnace at a suitable, point, so as to mix and combine with the zinc-vapors generated to form zinc sulfid, which is collected in a suitable separator, and thereby obtained in the form of an-impalpa ble powder. Instead of with sulfur-vapors the furnace may be sup' ammonium, and the like.

plied with suitable gaseous sulfur com- -poundssuch as sulfured hydrogen, sulfid of If desired the .sulfur-vapors may be generated within the furnace by suppl 'ng the samewith sulfur. If it is desired to o tain pure zinc-white in a finelyflocculent condition, oxygen or air or carbonic acid and the like is admitted'to the escaning zinc-vapors,- so as to burn them. In

a like manner gaseous compoundsof metals may be obtained-such for instance, as sodium-h drogenwhich is a very valuable material for filling ,aeros tats; In this instance my improved process is used for 811+. crating sodium-vapors from sodium-0X1 or carbonate, and during the generation of such vapors 'pure hydrogen is admitted; which .combines with the sodium-vapors. into' sodium hydrogen, or instead of water-gas may be used. i

I wish it to be -understood fthat the term metal as used inthe annexed claims is intended to comprise any metal capable of beingvolatilizedbyxmy process, that the term pure hydrogen incandescent fluid heat-carrier is intended to include any fluid obtained; by'melting and; heating the same .above their meltingpoint up to incandescence suitable solid substanoes,-. and that the term zinc ore is intended to include any natural "and artificial zinc compound, zinc-containing residues, tailings, and the like, treated either se arately or mixed with each other or with ot er compounds,

What I claim, anddesire to secure by Letter's Patent of the United States of America,

1 The described process which consists in bringing in contactwith' each other a compound or compounds of a metal or metals,- an

agent ca able 'of generating metallic va ors from sai com ound or compounds, an an incandescent uid heatscarrier, and leading off the vapors and gases for separation, substantially as described.

2'. The described process which consists in bringing in contact with each other a compound or compounds of a metal or metals, an

agent capable of. generating metallic va ors from said com ound or compounds, an an incandescent uid heat-carrier, admitting a gaseous agent to cause metallic compounds to be formed from the metallic vapors generated, and leading oil the mixture of vapors and gases for separation, substantially as described.

3: The described process which consists in bringing in contact with each other a compound or compounds of a metal or metals and-an incandescent fluid capable of generating metallic vapors from said compound or compounds, leading'off-the vapors and gases for separation, supplying the said fluid with heat and using it for decomposing a fresh IIO quantity of said compound or compounds, substantially as described.

4. The described process which consists in bringing in contact with each other a con1- pound or compounds of a metal or metals and an incandescent fluid capable of generating metallic vapors from said compound or compounds and of absorbing the sulfur contained therein, leading off the vapors and gases for separation, blowing air through the said fluid to heat it by the combustion of the sulfur absorbed and using it for decomposing a fresh quantity of compound or compounds, substantially as described. 7

5. The described process which consists in bringing Zinc ore in contact with carbon and an incandescent fluid heat-carrier, leading oil the zinc vapors and gases generated for condensation and separation, substantially as described.

6. The described process which consists in bringing zinc ore in contact with carbon and a molten silicate heated up to incandescence, and leading oil' the zinc vapors and gases generated for separation, substantially as described.

7. The described process Which consists in bringing zinc ore in contact with carbon and a molten silicate heated up to incandescence, admitting a gas for converting the zinc-vapors generated into vapors of a zinc compound, leading oil the vapors and gases generated for separation, substantially as de scri bod. I

H. The described process which consists in brin ing zinc ore in contact with carbon and a molten silicate heated up to incandescence, admitting air to convert the zinc-vapors nto seams vapors of zinc oxid, and leading ofi' the mix ture of zinc-oxid vapors and gases for separation, substantially as described. i

9. The described process which consists in adding zinc ore to a molten silicate heated up to incandescence, causing the mixture to ass through an excess of carbon, and lead mg oil the mixture of zinc vapors and uses for separation, substantially as describe 10. The described process which consists in adding zinc ore to a molten silicate heated up to incandescence, causing the mixture to pass through an excess of carbon, leading off the zinc vapors and gases for separation, collecting the outfiowing silicate, supplying it with a fresh quantity of zinc ore and with heat, and again bringing the mixture to contact with an excess of carbon, substantially as described.

11. The described process which consists in adding Zinc oreto a molten silicate heated up to incandescence, causing the mixture to pass through an excess of carbon, admitting air for converting the zinc-vapors generated into vapors of zinc oxid, leading oil the mix t'ure of zinc-oxid vapors and gases for separation, collecting the outflowing silicate, supplying it with a fresh quantity of zinc ore and with heat, and. again bringing the mixture in contact with carbon, substantially as tie-- scribed.

In testimony whereof I have hereunto set my hand in presence of two subscribing Wit-- WoLnEMAa HAUPT. 

